<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      div {
        width: 200px;
        height: 200px;
      }

      .box1 {
        background-color: skyblue;

        /* 隐藏，占位 */
        /* visibility: hidden;  */

        /* 隐藏，不占位 */
        display: none;
      }

      .box2 {
        background-color: orange;
      }
    </style>
  </head>
  <body>
    <div class="box box1">1</div>
    <div class="box box2">2</div>
  </body>
</html>
